1. Field of Invention
The invention relates to a communication device that is connected to a LAN (local area network) and/or a WAN (wide area network) and can perform a printing operation in accordance with a print request made by LAN terminals and/or WAN terminals through the LAN and/or WAN.
2. Description of Related Art
Japanese Laid-Open Patent Publication No. 2002-91739 (page 4 and FIG. 1) and Japanese Laid-Open Patent Publication No. 08-30692 (page 5 and FIG. 1) disclose a printing system in which a printer is connected to a LAN and/or a WAN. U.S. patent application Publication No. US 2002/0042884 (page 4 and FIG. 1) discloses a printing system in which an authenticated document is printed at a distant location by remote control.
A system has been suggested in which a printer is connected with a WAN, such as the Internet, as well as personal computers installed in a building or a house, via a LAN. In this system, the printer can be used by specific computers by performing authentication using, for example, passwords. However, this authentication confirms the identity of not only users on the WAN but also users on the LAN, so that this system has less usability. Also, a password may be artificially leaked to outsiders as well as being leaked by stealing packets from a network (sniffing). Accordingly, there is a possibility that unauthorized users can use the printer by using stolen passwords.